Every AYE verdict names the source class it was computed from. This page carries the attribution our upstream providers require.
Earthquake data is provided by the U.S. Geological Survey Earthquake Hazards Program (earthquake.usgs.gov). USGS makes no guarantee of accuracy or availability and is not affiliated with AYE.
Day-length verdicts are computed deterministically from published solar-position algorithms for the requested grid and date; no external feed is consulted.
Sources whose licenses are incompatible with commercial redistribution are quarantined before integration and only graduate after primary-text verification (see our research notes: Overture places data carry share-alike obligations; Open-Meteo's free tier is non-commercial and is therefore not used in production — EPA AirNow serves the air lane instead; Nominatim usage policies restrict heavy use). Each verdict's evidence payload includes a SHA-256 digest of the exact upstream bytes it was computed from.